Achieving Excellent Energy Storage Performance at Moderate Electric Field in Ca0.85bi0.05sm0.05tio3 Modified Bifeo3-Based Relaxor Ceramics Via Multiple Synergistic Design

•BF-BT-CBST ceramic exhibits excellent Wrec of 5.26 J/cm3 and η of 82.4% at 300 kV/cm.•Particularly high polarization of ∼ 41.5 μC/cm2 was maintained in BF-BT-CBST ceramic.•The addition of CBST enhanced the Eb and delayed the polarization saturation.•The BF-BT-CBST ceramic demonstrates superior discharge rate of t0.9 ∼ 27 ns.